Currently one has to consider what TV’s there are in use 4k/4k or 4k/1080p then lengths required. The HDMI cable type have limitations like 5m for a 4k TV and 15m for a 1080p TV, HDMI over Cat6 can be 40m for 4kTv and 70m to 1080p.
To use a mixture of both resolutions one must use what is called a downscaling splitter and they are limited to a few models, if not the 1080p TV more than likely will have a blank screen.
So far downscaling models are available, but as far as I know over 15m limited to 1×2, however we expect this to change in coming months with 1×4 HDMI over Cat splitters appearing in the market place. The best feature of using HDMI Cat is they come with IR device control, so for instance using a iQ3/4 then a simple conversion from Bluetooth to IR remote is all that is required or a former iQ2 remote will do the job.
The latest is this one a 1×2 but can be 1×3 and will run any configuration over HDMI Cat6 of 4k and 1080p TV’s.